The primary objective of this exploratory study is to determine multigenerational familial history (including emotional and physical pathology and marital, criminal, and death histories), among four groups of post-partum women: a heroin addict group in methadone maintenance treatment; a heroin addict group not in treatment; and two matched groups of post-partum non-addicts. A secondary objective is to obtain objective data on a population of neonates born to addicted mothers, as compared with neonates born of non-addicted mothers. Medical record examination will provide data on neonates. A third objective is to locate and identify neonates born to addicted mothers for longitudinal growth and developmental study. Information on three generations of each family will be obtained by interviewing post-partum women and maternal grandmothers, or maternal aunts. The sample will be made up of women serially admitted for care to the Baltimore City Hospitals Perinatal Narcotic Addiction Program. Other collaborative agencies which are expected to refer patients are: the University of Maryland Hospital and metropolitan Baltimore drug abuse treatment agencies. Patients will be matched with controls on a group of variables and will automatically be controlled for race. Data obtained should provide considerable information on the family pathology of the female addict and the addicted neonate. It will also provide follow-up accessibility to a population of neonates of addicted mothers, which may lead to further related research.